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From: "Robert I. Eachus" <eachus@mitre.org>
Subject: Re: Confusing language,
 was Re: Help help.. please.i am totaly new in  ada programing
Date: 1999/11/12
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Robert Dewar wrote:
  
> Note as a contrast Ada's view of how to store dates, which is
> completely hidden from the programmer. If you instantiate
> sequential I/O for a type with Calendar.Time in it, you get
> a tape full of highly implementation dependent data...

   Correct, but in Ada 95 the "right" way to create implementation
independent files is to use Streams.  If the vendor overrides 'Read,
'Write, 'Input and 'Output for Ada.Calendar.Time, which the vendor is
free to do, then
such times in files should be portable between programs running on
different system architectures.  It would be nice if the vendors could
get together on a single standard, but I don't think it can be added to
the Ada standard, since
streams are not required to be (8-bit) byte oriented.
 
>                          For example, the standard stream data in Ada is
> nowhere near being portable!

    I think that we need to bite the bullet, and not try to use streams
for too many things.  Streams should value portability over speed, while
direct and sequential files should be used where compatibility is not an
issue.  Or maybe we need multiple predefined stream types with different
characteristics.  But then there would have to be a way to query the
stream type.

-- 

                                        Robert I. Eachus

with Standard_Disclaimer;
use  Standard_Disclaimer;
function Message (Text: in Clever_Ideas) return Better_Ideas is...